Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756226Ab1CHWvP (ORCPT ); Tue, 8 Mar 2011 17:51:15 -0500 Received: from mx1.redhat.com ([209.132.183.28]:65298 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754961Ab1CHWvO (ORCPT ); Tue, 8 Mar 2011 17:51:14 -0500 Date: Tue, 8 Mar 2011 17:50:59 -0500 From: Vivek Goyal To: Justin TerAvest Cc: m-ikeda@ds.jp.nec.com, jaxboe@fusionio.com, linux-kernel@vger.kernel.org, ryov@valinux.co.jp, taka@valinux.co.jp, kamezawa.hiroyu@jp.fujitsu.com, righi.andrea@gmail.com, guijianfeng@cn.fujitsu.com, balbir@linux.vnet.ibm.com, ctalbott@google.com, nauman@google.com, mrubin@google.com Subject: Re: [RFC] [PATCH 0/6] Provide cgroup isolation for buffered writes. Message-ID: <20110308225059.GL27455@redhat.com> References: <1299619256-12661-1-git-send-email-teravest@google.com> <20110308224325.GK27455@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110308224325.GK27455@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3921 Lines: 88 On Tue, Mar 08, 2011 at 05:43:25PM -0500, Vivek Goyal wrote: > On Tue, Mar 08, 2011 at 01:20:50PM -0800, Justin TerAvest wrote: > > This patchset adds tracking to the page_cgroup structure for which cgroup has > > dirtied a page, and uses that information to provide isolation between > > cgroups performing writeback. > > > > Justin, > > So if somebody is trying to isolate a workload which does bunch of READS > and lots of buffered WRITES, this patchset should help in the sense that > all the heavy WRITES can be put into a separate cgroup of low weight? > > Other application which are primarily doing READS, direct WRITES or little > bit of buffered WRITES should still get good latencies if heavy writer > is isolated in a separate group? > > If yes, then this piece standalone can make sense. And once the other > piece/patches of memory cgroup dirty ratio and cgroup aware buffered > writeout come in, then one will be able to differentiate buffered writes > of different groups. Thinking more about it, currently anyway SYNC preempts the ASYNC. So the question would be will it help me enable get better isolation latencies of READS agains buffered WRITES? Thanks Vivek > > Thanks > Vivek > > > I know that there is some discussion to remove request descriptor limits > > entirely, but I included a patch to introduce per-cgroup limits to enable > > this functionality. Without it, we didn't see much isolation improvement. > > > > I think most of this material has been discussed on lkml previously, this is > > just another attempt to make a patchset that handles buffered writes for CFQ. > > > > There was a lot of previous discussion at: > > http://thread.gmane.org/gmane.linux.kernel/1007922 > > > > Thanks to Andrea Righi, Kamezawa Hiroyuki, Munehiro Ikeda, Nauman Rafique, > > and Vivek Goyal for work on previous versions of these patches. > > > > > > Documentation/block/biodoc.txt | 10 + > > block/blk-cgroup.c | 204 +++++++++++++++++++++- > > block/blk-cgroup.h | 9 +- > > block/blk-core.c | 216 +++++++++++++++-------- > > block/blk-settings.c | 2 +- > > block/blk-sysfs.c | 60 ++++--- > > block/cfq-iosched.c | 390 +++++++++++++++++++++++++++++++--------- > > block/cfq.h | 6 +- > > block/elevator.c | 11 +- > > fs/buffer.c | 2 + > > fs/direct-io.c | 2 + > > include/linux/blk_types.h | 2 + > > include/linux/blkdev.h | 81 ++++++++- > > include/linux/blkio-track.h | 89 +++++++++ > > include/linux/elevator.h | 14 ++- > > include/linux/iocontext.h | 1 + > > include/linux/memcontrol.h | 6 + > > include/linux/mmzone.h | 4 +- > > include/linux/page_cgroup.h | 12 +- > > init/Kconfig | 16 ++ > > mm/Makefile | 3 +- > > mm/bounce.c | 2 + > > mm/filemap.c | 2 + > > mm/memcontrol.c | 6 + > > mm/memory.c | 6 + > > mm/page-writeback.c | 14 ++- > > mm/page_cgroup.c | 29 ++- > > mm/swap_state.c | 2 + > > 28 files changed, 985 insertions(+), 216 deletions(-) > > > > [PATCH 1/6] Add IO cgroup tracking for buffered writes. > > [PATCH 2/6] Make async queues per cgroup. > > [PATCH 3/6] Modify CFQ to use IO tracking information. > > [PATCH 4/6] With per-cgroup async, don't special case queues. > > [PATCH 5/6] Add stat for per cgroup writeout done by flusher. > > [PATCH 6/6] Per cgroup request descriptor counts -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/